docs: def get_buckets(self, bucket_type=None, timeout=None):
          """
          Fetch a list of all buckets
          """
          bucket_type = self._get_bucket_type(bucket_type)
          url = self.bucket_list_path(bucket_type=bucket_type,
                                      timeout=timeout)
          status, headers, body = self._request('GET', url)
  
          if status == 200:
              props = json.loads(bytes_to_str(body))
              return props['buckets']
          else:
              raise RiakError('Error getting buckets.')